The invention relates to an apparatus for the insufflation of gas, particularly carbon dioxide, into the human or animal body, enabling the gas to be passed from a pressurized gas reservoir, preferably via one or more intermediate reservoirs, and at least one pressure reducer into a line and an insufflator, such as e.g. a Veress needle, the intraabdominal static pressure being measured by means of the apparatus.
Such a gas insufflation apparatus, is for example, known from German Pat. No. 28 03 646 and is used in particular to fill the abdominal cavity with gas in a controlled manner, so that endoscopic working is permitted or facilitated. It is necessary to keep the pressure constant within the abdominal cavity within physiologically acceptable limits and to accurately measure the same.
In the case of modern apparatuses of the aforementioned type, the gas is supplied to the abdominal cavity and the intraabdominal static pressure is measured by means of a single tube. According to the prior art, gas insufflation takes place intermittently and the gas flow is stopped during the intervals and the intraabdominal pressure directly measured. Although this method has proved satisfactory under various operating conditions, it still suffers from a number of disadvantages. Whilst gas is flowing into the abdominal cavity, the operator has no information on the actual pressure therein. Since during the aforementioned intermittent operation the blow-in times are much longer than the times during which the gas flow is stopped and the pressure measured, for relatively long periods the surgeon has no information on the existing static intraabdominal pressure.